"A compelling and invaluable account of life inside al-Qaeda through the eyes of a first-rate spy. This unique narrative throws open the shutters of the secret worlds of terror."--Lawrence Wright, bestselling author of The Looming Tower

As one of al-Qaeda's most respected scholars and bomb-makers, Aimen Dean rubbed shoulders with the mastermind of the 9/11 attacks and swore allegiance to Osama bin Laden himself. His job was already one of the most dangerous in the world. But what the others didn't know was that he was working undercover for MI6.

This is the story of a young Muslim determined to defend his faith, even if it meant dying for the cause, the terrible disillusionment that followed when he realised he was fighting on the wrong side, and the fateful decision to work undercover with his sworn enemy. In a career spanning decades in some of the most lethal conflicts of the past fifty years, we discover what it's like to be at the heart of the global jihad, and what it will take to stop it once and for all.